It is desired that missiles and bombs explode only when specified conditions are met, such as upon reaching their targets. Otherwise, it is desired that such missiles and bombs can be handled safely. Thus, it is necessary for a missile or bomb to contain a fuse that can differentiate between motions resulting from normal handling, or even severe accidental drops, and between the motions that indicate a need to set off an explosion, e.g., launch or impact. In addition, it is desirable that the operational readiness, as well as the state of the fuse, be testable with the result being perceivable by a human being.